Blunt neck trauma

Background

• Suspect vascular damage to cord if discrepancy between neuro deficit and level of spinal column injury
• Down syndome predisposes to atlanto-occipital dislocation
• RA predisposes to C2 transverse ligament rupture
• Cord injury is more likely if ant (vertebral bodies) AND post (spinal canal) columns are disrupted
• If find injury consider CT C-spine, x-ray rest of spine
• Penetrating injury rarely results in unstable fx

Atlanto-occipital Disassociation

• Unstable
• Evaluate with the Powers ratio
  • Ratio of BC:OA > 1 suggests anterior subluxation
  • BC = distance between basion and midpoint of C2 post laminar line
  • OA = Distance between opisthion and ant arch of C2

C1 Fractures

Burst (Jefferson)

• Unstable
• Axial loading transmitted through occipital condyles to the lateral masses
  • Results in fx of the ant AND post arches
  • Degree of instability determined by whether or not the transverse ligament is disrupted
• Suspect disruption if:
  • Lateral x-ray: Increase in the predental space between C1 and the dens
    • Predental space greater than 3 mm in adults or 5 mm in children is abnormal
  • Odontoid xray: Masses of C1 lie lateral to outer margins of articular pillars of C2
  • If either of the above findings on xray then obtain CT c-spine

Anterior Arch

• Stable

Posterior Arch

• Stable (b/c anterior arch and transverse ligament are unaffected)
• Must ensure that you are not confusing this with a burst fx
  • Odontoid view must be normal
• Due to forced neck extension
• Vertical fx line through posterior arch seen on lateral xray

C2 Fractures

Odontoid (dens) Fracture

• Only stable if fx confined to avulsion of the tip (superior to transverse ligament)
• Frequently involves other cervical spine injuries
• 25% a/w neurologic injury

Traumatic Spondylolisthesis ("Hangman's Fx")

• Unstable
• Fracture of both C2 pedicles leads to C2 displacing anteriorly on C3
• Seen in MVA and diving accidents (not in suicidal hangings)
  • Forced extension of an already extended neck
• Spinal cord damage is often minimal (diameter of neural canal is greatest at C2)

Cervical Fractures

Anterior Wedge Fracture

• Only unstable if:
  • Loss of over half of vertebral height OR multiple adjacent wedge fractures

Flexion Teardrop Fracture

• Unstable
• Displacement of teardrop shaped fragment of antero-inferior portion of superior vertebra
  • Severe flexion > vertebral body colliding with the one below
• Associated with acute anterior cervical cord syndrome due to fx-induced kyphosis

Extension Teardrop Fracture

• Unstable
• Abrupt neck extension > anterior longitudinal ligament avulses anteroinferior corner
  • Avulsed fragment is greater in height than width (contrast with flexion teardrop)
• Often occurs at C5-C7 associated with diving accidents
  • Associated with central cord syndrome

Spinous Process Fracture (Clay Shoveler's)

• Stable
• Isolated fracture of one of the spinous processes of the lower cervical vertebrae

Burst Fracture

• Unstable
• Axial compression > nucleus pulposus forced into vertebral body
• Posteriorly displaced fracture fragment may impinge on the cord
• Imaging
  • Lateral xray - Comminuted body and loss of vertebral height
  • AP xray - Vertical fracture of the body

Facet Dislocations

Bilateral

• Unstable
• Complete spinal cord injury most often results
• Disruption of annulus fibrosus and ant longitudinal ligament > ant displacement of spine
• Imaging
  • Lateral xray: vertebral body will be displaced >50% of its width

Unilateral

• Stable
• Imaging
  • Lateral xray: vertebral body will be displaced <50% of its width
  • Anterior xray: affected spinous process points toward side that is dislocated
• Spinal cord injury rarely occurs

See Also

• Spinal Cord Trauma
• Spinal Cord Compression (Non-Traumatic)
• Neurogenic Shock
• C-spine (NEXUS)
• C-Spine X-Ray

Source

• UpToDate
• Tintinalli's